Structurally conserved α-neurotoxin genes encode functionally diverse proteins in the venom of Naja sputatrix11The genomic DNA sequences (WNTXs and LNTX) reported in this paper can be accessed from the GenBank with accession numbers AY081759 to AY081763 and AF026893 for the LNTX-7 cDNA sequence.

Autor: Jeyaseelan, Kandiah, Poh, Siew Lay, Nair, Ramkishen, Armugam, Arunmozhiarasi
Předmět:
Zdroj: FEBS Letters; Oct2003, Vol. 553 Issue 3, p333, 9p
Abstrakt: The structure and organization of the genes encoding the long-chain neurotoxins and four other isoforms of weak neurotoxins in the venom of Naja sputatrix are reported. The genes contained three exons interrupted by two introns, a structure similar to other members of the three-finger toxin family. The proteins encoded by these genes, however, show varied affinity towards nicotinic acetylcholine receptors. Phylogenetic analysis of these genes showed that the weak neurotoxin gene is confined to a distinct group. We also observe that specific mutations of the gene provide the diversity in function in these toxins while maintaining a common structural scaffold. This forms the first report where the molecular basis of evolution of postsynaptic neurotoxins from an ancestral gene can be demonstrated using the same species of snake. [Copyright &y& Elsevier]
Databáze: Complementary Index